[1.3.1] Ferram Aerospace Research: v0.15.9.1 "Liepmann" 4/2/18

[MNSRSkittles]

here is the new version, and it still does the same thing.

Here's my CRAFT file if anyone wants to help see what the problem is.

You'll need Life support, procedural fairings and obviously FAR.

http://puu.sh/8cvDf.craft

Edited April 17, 2014 by MNSRSkittles

[ferram4]

@Dragon01: It's my own, built using config tweaks for the engines to get exact performance (according to Astronautix anyway) and stretchies + pFairings for the shape. I'll probably release it in the Realism Overhaul thread once I have it account for the H2O2 to run the pumps properly, and once I get the boosters to separate closer to the way they should. Currently, the top pops away too quickly, so I think I'll add a thrust ramp-up delay on the LOX valves to compensate. Especially since it includes functional verniers, and I know the realism fans like that sort of stuff.

@Aedile: Aerobraking itself should be fine. Mad aerocaptures from 7 km/s entering Kerbin's SOI, not so much.

@localSol: Fairings are pFairings, based on blackheart's changes, and colored orange. Tanks are stretchies (see StretchySRB or Procedural Parts), using the included SoyuzGreen and White textures.

@MNSRSkittles: That looks like an awful lot of thrust for the payload you've got there; you could probably benefit from reducing the TWR, which would make the rocket a little more stable. Turn earlier than you're used to.

Another thing to look at is how much empty space is in your fairing; that means that the fairing is making a lot of lift / drag, but there's no mass inside to compensate. Get rid of the 3.75-2.5m adapter so you can use the "R" button to downscale the pFairings to a reasonable size. You might also want to shift the LVT-30/45 boosters on the payload forward a little bit to shift the CoM further forward to make the craft more stable. Consider shifting the Monopropellant tanks into the fairing, where they won't make any drag. Finally, consider adding fins if it seems necessary.

[MNSRSkittles]

@Dragon01: It's my own, built using config tweaks for the engines to get exact performance (according to Astronautix anyway) and stretchies + pFairings for the shape. I'll probably release it in the Realism Overhaul thread once I have it account for the H2O2 to run the pumps properly, and once I get the boosters to separate closer to the way they should. Currently, the top pops away too quickly, so I think I'll add a thrust ramp-up delay on the LOX valves to compensate. Especially since it includes functional verniers, and I know the realism fans like that sort of stuff.

@Aedile: Aerobraking itself should be fine. Mad aerocaptures from 7 km/s entering Kerbin's SOI, not so much.

@localSol: Fairings are pFairings, based on blackheart's changes, and colored orange. Tanks are stretchies (see StretchySRB or Procedural Parts), using the included SoyuzGreen and White textures.

@MNSRSkittles: That looks like an awful lot of thrust for the payload you've got there; you could probably benefit from reducing the TWR, which would make the rocket a little more stable. Turn earlier than you're used to.

Another thing to look at is how much empty space is in your fairing; that means that the fairing is making a lot of lift / drag, but there's no mass inside to compensate. Get rid of the 3.75-2.5m adapter so you can use the "R" button to downscale the pFairings to a reasonable size. You might also want to shift the LVT-30/45 boosters on the payload forward a little bit to shift the CoM further forward to make the craft more stable. Consider shifting the Monopropellant tanks into the fairing, where they won't make any drag. Finally, consider adding fins if it seems necessary.

I did not know you could resize fairings, I've played with them for about an hour, thanks a bunch! EDIT: Pressing R does nothing, what am I doing wrong?

Edited April 17, 2014 by MNSRSkittles

[Starstrider42]

I did not know you could resize fairings, I've played with them for about an hour, thanks a bunch! EDIT: Pressing R does nothing, what am I doing wrong?

Hold R while dragging the mouse up/down or left/right while over the fairing adapter (not the fairing itself). Same goes for other key combinations; you can get a full list by right-clicking on the fairing adapter in the parts list.

[MNSRSkittles]

Ah okay thanks, what is Auto Struts by the way?

[criminy]

Ah okay thanks, what is Auto Struts by the way?

It toggles whether struts are added between the payload and the pFairings.

[NavyFish]

Hello folks. I've recently started using FAR, and all I can say is wow. What a difference!

I seem to have a bit of a bug on my hands, however. The Editor Analysis graphs won't plot anything, either via sweep Mach or sweep AOA. I've tried all varieties of upper and lower bounds, flap settings, updated the CoL, etc. No joy. Any advice?

I'm using b9 with the .23.5 community patch, could this be the issue? Also using KW Rocketry and KSP-Interstellar, but that's about it for part mods.

-Navy

[AndreyATGB]

Hello folks. I've recently started using FAR, and all I can say is wow. What a difference!

I seem to have a bit of a bug on my hands, however. The Editor Analysis graphs won't plot anything, either via sweep Mach or sweep AOA. I've tried all varieties of upper and lower bounds, flap settings, updated the CoL, etc. No joy. Any advice?

I'm using b9 with the .23.5 community patch, could this be the issue? Also using KW Rocketry and KSP-Interstellar, but that's about it for part mods.

-Navy

First off, I love your docking alignment mod, just great. And for the editor issue, pics are usually a must in this thread so a picture of your craft with the menu open is helpful.

[ferram4]

@NavyFish: Post a copy of your output_log.txt, something might be breaking in there.

[NavyFish]

Sure enough, there are a whole slew of errors in my output log:

FAR Error: Aerodynamic force = NaN AC Loc = 10.94645 AoA = 0

MAC = 1.587 B_2 = 1.695 sweepAngle = 0

MidChordSweep = 22.1 MidChordSweepSideways = 0.1689623

 at winglet3


FAR Error: Aerodynamic force = NaN AC Loc = 9.932593 AoA = 0

MAC = 1.6 B_2 = 1.963 sweepAngle = 0

MidChordSweep = 12.09 MidChordSweepSideways = 0.1016958

 at B9.Aero.Wing.SW.Canard.2-3x1-6m

This continues for several thousand lines, after which point I get:

DivideByZeroException: Division by zero
  at ferram4.ferramGraph.GridInit (Int32 widthSize, Int32 heightSize) [0x00000] in <filename unknown>:0 

  at ferram4.ferramGraph.SetGridScaleUsingPixels (Int32 gridWidth, Int32 gridHeight) [0x00000] in <filename unknown>:0 

  at ferram4.ferramGraph.SetGridScaleUsingValues (Single gridWidth, Single gridHeight) [0x00000] in <filename unknown>:0 

  at ferram4.FAREditorGUI.UpdateGraph (System.Single[] AlphaValues, System.Single[] ClValues, System.Single[] CdValues, System.Single[] CmValues, System.Single[] LDValues, System.String horizontalLabel) [0x00000] in <filename unknown>:0 

  at ferram4.FAREditorGUI.AngleOfAttackSweep (Single M, Single pitch) [0x00000] in <filename unknown>:0 

  at ferram4.FAREditorGUI.GraphGUI (Boolean tmp) [0x00000] in <filename unknown>:0 

  at ferram4.FAREditorGUI.ActualGUI (Int32 windowID) [0x00000] in <filename unknown>:0 

  at UnityEngine.GUILayout+LayoutedWindow.DoWindow (Int32 windowID) [0x00000] in <filename unknown>:0 

  at UnityEngine.GUI.CallWindowDelegate (UnityEngine.WindowFunction func, Int32 id, UnityEngine.GUISkin _skin, Int32 forceRect, Single width, Single height, UnityEngine.GUIStyle style) [0x00000] in <filename unknown>:0 

(Filename:  Line: -1)

Mass: NaN

S: 48.25777

MAC: 1.925892

I'll post the log in a moment so you can check it out.. upload speed here is quite slow and it's a 13mb file.

Thanks for the fast response!!

[NavyFish]

output log: http://www1.zippyshare.com/v/11465606/file.html (click the orange 'download now' button)

[KvickFlygarn87]

Can someone explain to me in detail how to do a gravity turn in this mod?

[BudgetHedgehog]

Can someone explain to me in detail how to do a gravity turn in this mod?

Have a rocket with about 1.2 TWR at launch. When you're travelling between 60 and 100 m/s start pitching over SLOWLY - you'll want to be 45 degrees at about 10km and horizontal at 40 or so. Keep your time to apoapsis at about a minute. Never, under any circumstances, do the stock "straight up then 45 degrees at 10km" so-called gravity turn - you'll flip out and not go to space today. Small gradual increments are the way to go.

Your ship design influences the turn greatly. You'll need a heavy and low drag top and a (as light as you can make it) high drag bottom. Nosecones, fairings and fins help with these. Ideally the rocket should be pretty long and reasonably thin (that means no more asparagus! Not that you'll really need it any more though). If you design it right, once you're pitched over about 10 degrees, you can actually turn of SAS and the rocket will turn perfectly in time and you don't even need to touch the WASD keys until you're into thinner air.

Edited April 18, 2014 by ObsessedWithKSP

[KvickFlygarn87]

Yay! I managed to get into orbit just fine! Thanks, ObsessedWithKSP!

[BudgetHedgehog]

Yay! I managed to get into orbit just fine! Thanks, ObsessedWithKSP!

You're welcome! It'll quickly become habit and then, for laughs, you can try on a clean install and wonder how you ever managed to fly in that soup stock calls an atmosphere

[ferram4]

@NavyFish: I found the error; it's actually not on FAR's side, it's merely a consequence of the NaN/ElectricCharge bug. When that bug occurs, it sets the mass of the part to NaN, which them propagates through all of the calculations, corrupting everything it touches.

I believe that there is a fix for it floating around somewhere; I wish I could point you to it, but I only remember skimming over it at some point.

[BudgetHedgehog]

@NavyFish: I found the error; it's actually not on FAR's side, it's merely a consequence of the NaN/ElectricCharge bug. When that bug occurs, it sets the mass of the part to NaN, which them propagates through all of the calculations, corrupting everything it touches.

I believe that there is a fix for it floating around somewhere; I wish I could point you to it, but I only remember skimming over it at some point.

This?

@PART[*]:HAS[@MODULE[ModuleEngines],@RESOURCE[ElectricCharge]]
{
	@RESOURCE[ElectricCharge]
	{
		%isTweakable = false
		%hideFlow = true
	}
}

[NathanKell]

Yup, that one. I'm thinking now maybe I should have been detecting ModuleAlternator instead, but it seems fine.

[NavyFish]

Gents,

Thank you for the team effort. Awesome!

I won't be in a position to test out the fix until tomorrow morning, but am excited and confident to do so.

I'm sure it's been said countless times already but - excellent work on this mod. It's inspiring to see how much of an impact one mod can have on such a core element of gameplay.

-Navy

P.S. - I'm assuming one should drop this text into a new config file "EngineElectricChargeFix.cfg" (or similar) file under GameData? asking mostly for others' future reference.

Edited April 18, 2014 by NavyFish

[Bekiekutmoar]

Great mod ... ! I'm gradually getting the hang of it. As a matter of fact, I'm planning a return mission from Eve with FAR. I've read somewhere that Delta-V requirements to reach LKO from the surface is actually lower than without FAR, provided one pilots a tall and aerodynamical rocket. I assume this isn't much different on Eve. Now, what if I ascended from the Evian surface at 2-3 km above what passes for sea-level, I would still need ... 5-6 km Delta-V ... ? So I could suffice with only a moderately large lander massing a 'mere' 30-40 tonnes (with Mk1 Pod) ... ?

[NathanKell]

NavyFish: yup! Can stick it anywhere under GameData that's not a PluginData folder (GameDatabase loads all cfg, mu, dae, and images from GameData, as long as they're not in/under a PluginData folder).

[ferram4]

@Bekiekutmoar: I think it would be somewhere around 5.5 km/s of dV, based on low Eve orbital velocity (~3.5 km/s), the gravity well (probably ~1.5 - 2 km/s) and then atmospheric drag (for Kerbin, it's ~100 m/s; I'd scale it with air pressure, so ~500 m/s). So then bring margin.

The real trick is to have a rocket that will be stable while landing that will also be stable during takeoff, since they'll probably want to flip. Also, your terminal velocity will be relatively high; in RSS, on Venus (so only ~1g of gravity, but 92 atm of pressure) macallo had a rocket that had a terminal velocity of 150 m/s, so on Eve it will be much higher, since higher gravity and lower air pressure. You'll need a decently sized descent stage.

[AndreyATGB]

I can tell you right now that building a traditional rocket that is capable of flying in both directions is NOT fun. It took really long to get something decent figured out(it was for Laythe) but I just scrapped it and used my SSTO.

[Bekiekutmoar]

Hmmm, stability issues seem to form a problem indeed ... ! I'm think about various solutions ... Perhaps turning the rocket into a giant dart to Ensure stable entry into the thick Evian atmosphere. Seems like an interesting challenge ... !

[Dust]

I'm using v0.13.1. I seem to have a problem with rockets flipping when I build them tall - they're fine at first but up a few km they flip tail over nose as soon as the nose diverts a few degrees from surface prograde. This, by the way, is following a gradual gravity-turn-like ascent profile including throttling down to maintain efficient airspeed. The only way to combat this is to load up the rear with fins, which I'd rather not have to do.

The other day it dawned on me that it seems to be because fuel empties from top to bottom - which results in the top getting lighter, the CoM dropping, and creating a situation where the nose of my rocket would much rather be trailing. I confirmed it by transferring fuel up during ascent and stability was preserved.

Is this truly a significant factor in this behavior, or are there other factors at play to be more concerned with? And if my observations are correct, is there any known way of changing fuel behavior to empty tanks from the bottom up instead?